Five Great .270 Cartridges
May 28, 2019
During most of its 93 years of existence, the .270 Winchester has been quite popular among hunters, and for as long as I can remember, it has made the Top Five big-game cartridge list at RCBS, according to reloading die sales. So why only a few other cartridges of its caliber have been introduced through the years has long been a mystery. Here’s a brief look at the old-timer followed by four newer cartridges that share its bullet diameter—including the as yet to be introduced 27 Nosler.
Two questions about the .270 Win. will likely forever remain unanswered. Why did its designers neck down the .30-03 case and not the slightly shorter .30-06 case, which had replaced it 19 years before the .270 Win. was introduced in 1925? And why did they go with the odd bullet diameter of 0.277 inch when 0.264- and 0.284-inch bullets had been extremely popular in other countries for quite a few years? I won’t speculate on why the .30-03 case was used, but my best guess on bullet diameter is that they wanted the cartridge to be different from anything else of American design. The .256 Newton loaded with a 0.264-inch bullet was enjoying a bit of popularity among hunters, and giving the .270 Win. a slightly bigger case and a slightly fatter bullet may have been a bit of one-upmanship at a time when new cartridges were not introduced on a weekly basis.
The .270 was introduced in the Winchester Model 54, but it was not an instant success. In those days the few firearms writers working regularly were big fans of the .30-06, and little positive mention was made of the new upstart. Some figured the .270 was too small for use on anything but deer. Others opined that its high velocity would be too destructive on steaks and chops. Then a college professor by the name of Jack O’Connor bought a Model 54 in .270 and later had a number of custom rifles on Model 70 actions built around it as well. O’Connor proved to the hunting world that the .270 was capable of cleanly taking game as large as moose and elk.
I became a big O’Connor fan during my youth, but I did not get around to hunting with the .270 until the early 1960s. I eventually shot enough game with the cartridge to learn a thing or two about its performance. O’Connor was right about it being big enough medicine for elk, but even he admitted that the .30-06 is a better elk cartridge. For everything else walking the North American continent on hooves, the .270 will do anything any ethical hunter needs to get done.
O’Connor was also right about powder and bullet weight. H4831 is still the powder to beat, although it does have plenty of competition today. Everything considered, 130 grains has proven to be the ideal bullet weight, although I have often moved up to 150 grains when in elk country. The Nosler 160-grain Partition is probably the most neglected. It’s not pretty and it’s not all that fast, but you can believe me when I say it does a great job on Alaska-Yukon moose.
My favorite .270 rifles today are a Model 70 Featherweight built by Winchester in 1959 and a Remington Model 700 American Wilderness Rifle with a 24-inch barrel. The Model 70 is my bluebird weather rifle, and the Model 700 is for rainy-day hunts. The Remington is more accurate, but the Winchester is accurate enough to take game as far away as I care to shoot.
.270 Weatherby Magnum
Roy Weatherby introduced his first big-game cartridge, the .270 Weatherby Magnum, in 1943 and began offering handloaded ammunition in 1945. When loaded with IMR 4350, the slowest-burning powder available at the time, the .270 Wby. Mag. was not a lot faster than the .270 Win. when both were loaded to the same chamber pressure. That changed somewhat after Bruce Hodgdon introduced military-surplus H4831 in 1950.
Weatherby rifles chambered for most of the Weatherby cartridges have always had freebored chambers that allow bullets to freetravel quite a long distance prior to engaging the rifling. This allows an increase in powder charge weight for higher velocity at no increase in chamber pressure. Throat length was originally 0.750 inch, and it was shortened to 0.500 inch during the late 1970s. The 1:12 rifling twist of early .270 Wby. Mag. rifles is too slow to stabilize some of today’s bullets, but later rifles with a 1:10 twist handle most of them just fine.
While velocity can be increased with a freebored chamber, the long jump makes some rifles particular about the bullets they will shoot accurately. For this reason, reamers that cut a standard-length throat have been used when building custom rifles around the various Weatherby cartridges. A rifle so chambered is more likely to shoot a variety of bullet types more accurately, but maximum velocities attainable at acceptable chamber pressures will fall about 100 fps short of what is possible with a freebored chamber. I mention this because if one of those rifles is purchased on the used-gun market, a couple of things should be kept in mind. Factory ammo is loaded to chamber pressures that are quite safe in a freebored chamber but will likely generate excessive pressures when fired in a rifle with a standard chamber. The same applies to some of the maximum loads published in various reloading manuals.
HSM, Federal, Nosler, and Weatherby offer .270 Wby. Mag. ammunition. Unprimed cases are available from Hornady, Nosler, Norma, and Weatherby. H4831 is a good starting point, although slower powders sometimes deliver higher velocities with 150- and 160-grain bullets. Expanding bullets of monolithic construction often shoot more accurately when seated for plenty of jump, and that makes those from Barnes, Hornady, Nosler, and others logical options for rifles with freebored chambers.
I have owned a Weatherby Mark V Deluxe in .270 Wby. Mag. since 1984. It still wears the Weatherby 3-9X Supreme scope in a Buehler two-piece mount that came on it. My name was engraved on a gold plate inletted into the bottom of its fore-end, and the rifle was presented to me on a special occasion by Roy Weatherby. While I am sure he would have wanted me to take it hunting, I simply could not bring myself to subject it to the hard knocks of the outdoors. But I have hunted enough with other rifles chambered for his .270 to know it to be capable of doing anything that can be done with a rifle chambered for one of the 7mm Magnums.
A few months prior to the official introduction of the .270 WSM in 2002, I used a Browning A-Bolt chambered for it to take a very large nilgai bull on the King Ranch in Texas. What has to be the most bullet-proof animal in North America took one 140-grain bullet behind its shoulder at 160 yards and immediately went down for the count. During that year, I used the same rifle to take mule deer, pronghorn antelope, elk, and caribou, and they also were one-shot kills. I have not kept an accurate count of the game bagged with the .270 WSM through the years, but I have taken enough to become convinced that all things considered—including recoil and performance on game—it might just be the most useful member of the WSM family.
When first introduced, there was quite a bit of speculation on how much faster it is than the .270 Win. Data published in various reloading manuals answer that question. I averaged maximum velocities for three bullet weights listed in the latest reloading manuals published by Lyman, Speer, Barnes, Hornady, Western Powders, Hodgdon, Swift, Berger, Nosler, and Sierra. If data for the two cartridges in a particular manual were developed in barrels of different lengths, I compensated by adding 25 fps per inch for the shorter barrel.
Average maximum velocities for 130-grain bullets were 3,158 fps for the .270 Win. and 3,302 fps for the .270 WSM for a difference in favor of the .270 WSM of 144 fps. Averages for 140-grain bullets were 3,034 fps and 3,176 fps respectively for a difference of 142 fps. Averages for 150-grain bullets were 2,926 fps and 3,085 fps respectively for a difference of 159 fps.
I still occasionally hunt with my two .270 Win. rifles, but anytime tall mountains are to be climbed, a lighter rifle will hang from my shoulder. One of my favorites is a Browning A-Bolt Mountain Ti in .270 WSM. Mine weighs 5.25 pounds, and a Swarovski 3-10X scope in a Talley lightweight mount adds only about a pound. My first one was in .300 WSM, and after using it to take an outstanding elk in the mountains of New Mexico, I decided just one was not enough. Soon after the A-Bolt was dropped from production, I spotted a new-in-the-box Mountain Ti in .270 WSM at a gunshop at a drastically reduced price and could not resist bringing it home.
Federal, Hornady, HSM, Nosler, Barnes, Remington, DoubleTap, and Winchester offer .270 WSM ammunition. Unprimed cases are available from Hornady, Nosler, Federal, Remington, and Winchester. Depending on bullet weight, powders with burn rates ranging from H4831 to Retumbo are viable candidates.
Designed in about 2002, the 6.8 SPC was intended for use in the M16/AR-15, but the rifles I have used in the field are bolt actions and a custom T/C Contender single-shot rifle built by SSK Industries. In 2004 I hunted caribou in Canada, and because two bulls could be taken legally, I took along two Remington 700 rifles, one in 7mm Remington Magnum, the other in 6.8 SPC. My 6.8 ammo was loaded with Remington’s 115-grain Core-Lokt Ultra bullet at 2,650 fps. Residual energy at 200 yards was about the same as for the .30-30 Winchester at 100 yards, and because the .30-30 in the hands of native Alaskans has taken thousands of caribou through the years, I figured the 6.8 was plenty for shots no farther away than 200 long paces. I was right.
The Model 700 I used to take a caribou had a 20-inch barrel and was a preproduction rifle built specifically for that hunt. Soon thereafter, Remington added the 6.8 chambering to the Model Seven, and during the following years, it was available in several variants of the Model Seven and the Model 700. The most accurate I shot was a Model 700 SPS with a 22-inch barrel. A few AR-15s have been available—and still are available—in 6.8 SPC. Due to an extremely high expansion ratio, the little cartridge does not gain a lot of velocity as barrel length is increased beyond 18.5 inches.
The 6.8 SPC was introduced with great fanfare, and although it now appears to be struggling, plenty of rifles chambered for it are still being shot. Federal, Hornady, Remington, SSA, Sellier & Bellot, and Prvi Partizan offer it, so there is no shortage of ammo. Among the factory loads, my favorite varmint load is Federal American Eagle loaded with the Speer 90-grain TNT. A friend of mine bought a Model Seven in 6.8 SPC as a first centerfire rifle for his young daughter, and he considers Hornady Custom with the 120-grain SST and Federal Fusion with the 115-grain Fusion to be the deadliest medicines available for use on deer and feral hogs.
Neither is there a shortage of reloading components. Brass is available from Hornady, Nosler, and Starline, and expanding bullets designed specifically for use in the 6.8 SPC are available from Barnes, Speer, Hornady, Nosler, and Sierra. A number of powders have the correct burn rate for this cartridge, with CFE BLK, Accurate 1680, and Power Pro 1200R among the best choices.
Soon after Mike Lake of Nosler had completed the designs and specifications for a family of cartridges on the .404 Jeffery case, they were all registered with SAAMI. The 26 Nosler introduced in 2013 was followed by the 28 Nosler in 2015, the 30 Nosler in 2016, and the 33 Nosler in 2017. His other creations waiting impatiently in the wings are the 27 Nosler, the 35 Nosler, and the 36 Nosler.
I was especially interested in the 27 Nosler, and while there are no immediate plans to offer unprimed cases, ammunition, or rifles chambered for it, my friends at Nosler kindly agreed to build a Model 48 Liberty in 27 Nosler for this report. It weighed 8 pounds, 13.5 ounces with a Bushnell 1.5-6X Elite 4200 scope in a Talley lightweight mount. Its 26-inch Shilen barrel measured 1.15 inches at the receiver, and from there it tapered to a muzzle diameter of 0.635 inch. A 1:10 rifling twist rate proved to be quick enough to stabilize the rather long 150-grain AccuBond LR, but even longer bullets are available. Should Nosler eventually move forward with production rifles chambered for this cartridge, a 1:8 twist would be in order.
The 27 Nosler case is easily formed by necking down 30 Nosler brass. I used an RCBS die set and first tried running a case through the full-length resizing die with its mouth in contact with the shellholder. The bolt would close and lock up on a case, but the fit was a bit too snug. I then lowered the ram and turned in the die just enough to force the RCBS Rock Chucker press to cam slightly over center when the ram was fully raised. Cases sized in that manner allowed the bolt to close and lock up with only light resistance. It proved to be excellent brass. Neck length increased only slightly after cases had been pounded by four full-power firings. Cartridge neck diameter with a bullet seated is 0.311 inch. Gross water capacity is 104.6 grains versus 83.1 grains for .270 Wby. Mag. cases made by Nosler.
Considering its big appetite for powder, velocity spread with the 27 Nosler was quite low. IMR 7977 and IMR 7828 proved to be excellent choices behind 130-grain bullets, and when burned behind 140- and 150-grain bullets, Retumbo proved to be up to the task in both accuracy and velocity. Reloder 50 did a good job behind the Nosler 160-grain Partition, and H50BMG and US 869 would likely do as well. Other likely candidates for this cartridge include IMR 8133, Reloder 33, Reloder 25, and Reloder 26.
SAAMI average maximum pressure for the 27 Nosler is 65,000 psi. The loads for 140- and 150-grain bullets in my chart were furnished by Nosler and did not exceed 61,750 psi in Nosler’s 26-inch pressure barrel. I developed the loads for 130- and 160-grain bullets, and while they have not been pressure-tested, they were safe maximums in my rifle. Pacific Tool & Gauge has chamber reamers for all Nosler cartridges, including the 27 Nosler, 35 Nosler, and 36 Nosler.
Nosler has committed to supporting the new cartridge with load data to be published in 2019, but there are no intentions to offer brass or loaded ammunition at this time. The 27 Nosler has the potential to be a real winner, so if enough riflemen ask for it, Nosler could very possibly change that policy. Time will tell.